<!DOCTYPE html>
<html>
<head lang="en">
    <meta charset="UTF-8">
    <title>JS输出语句</title>
</head>
<body>
<script>
    document.write("在页面输出内容");
    console.log("控制台调试信息");
    alert("弹出框提示信息");
</script>
</body>
</html>